I typically do 1 batch = 1 8" round, but you could do a 9" it would just be thinner. For an 8" I bake at 350 for about 25-30 minutes, but different recipes and different ovens will obviously need some adjustment. A 9" round will take less time due to being thinner.

to hijack this thread a wee bit - I wonder what will happen if I make one of the VCTOTW recipes into a 6inch cake instead of 8 or 9. BF always wants 2layer cakes because that means more frosting per bite I guess (I'm definitely not a frosting fan), but a) we don't need a full double-layer cake! and b) I don't always have luck horizontally splitting an 8inch cake levelly so I'm looking to thicken the layer more! know I'll have to play with the baking time, but I just got a 6inch heart pan and I'm gonna be trying this out.

A 6" heart will probably only take 1 1/2 cups of batter, maybe 2 at the most depending on the pan. Be careful not to over-fill, trust me. You will not only end up with a mess in your oven, but you will end up with a simultaneously burnt and soggy underdone rock of a cake. Measure how much water will fill the pan to the brim, then use no more than 2/3 that of cake batter, and turn the rest into cupcakes.